A tweed, Princeton Reverb or Deluxe Reverb. You could potentially 'outgrow' the
PR, but it would still serve you well for a long while.
One thing to keep in mind; this doesn't have to be just the first in a long line of tube amp purchases. If chosen wisely, you would never need to go looking for another amp.
A couple of principles to keep in mind while your looking.
1. Any guitar will sound good when plugged into a good amp. But that $3K Les Paul will sound terrible plugged into a bad amp.
2. There is no quiet tube amp. Sorry, but even a Champ is going to be pretty loud. Adjust your or your wife's expectations accordingly.
3. An amp IS an instrument. It is not a piece of equipment. As such, no two amps of the same brand and model are the same. Each responds to your input differently, albeit slightly, but still differently.
4. You're going to play a lot of amps. Adjust your expectations accordingly. When you find the right one, you'll know it. Hopefully the salesman won't know it, otherwise you'll be at a distinct disadvantage when trying to negotiate a price (only suckers pay retail).
5. If you do find 'your' amp, it will likely be the only amp you ever need.
Good luck and enjoy the journey. It's a long road. Adjust your expectations accordingly.